WeakPtr destruction order cleanup: media edition.

media/filters/ffmpeg_demuxer.h

Index: media/filters/ffmpeg_demuxer.h
diff --git a/media/filters/ffmpeg_demuxer.h b/media/filters/ffmpeg_demuxer.h
index 6445ed7876e0212d5eb892b01f3bc4bbc34172d9..6068e0d90038641485a85de5c2da0fbe4120b255 100644
--- a/media/filters/ffmpeg_demuxer.h
+++ b/media/filters/ffmpeg_demuxer.h
@@ -205,8 +205,6 @@ class MEDIA_EXPORT FFmpegDemuxer : public Demuxer {
   DemuxerHost* host_;
 
   scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
-  base::WeakPtrFactory<FFmpegDemuxer> weak_factory_;
-  base::WeakPtr<FFmpegDemuxer> weak_this_;
 
   // Thread on which all blocking FFmpeg operations are executed.
   base::Thread blocking_thread_;
@@ -264,6 +262,9 @@ class MEDIA_EXPORT FFmpegDemuxer : public Demuxer {
 
   const NeedKeyCB need_key_cb_;
 
+  // NOTE: Weak pointers must be invalidated before all other member variables.
+  base::WeakPtrFactory<FFmpegDemuxer> weak_factory_;
+
   DISALLOW_COPY_AND_ASSIGN(FFmpegDemuxer);
 };